This invention relates to an improved back pack support apparatus for concentrating weight of the pack at the lumbar area of a wearer's spine.
In the past, adjustable harnesses have been used to transfer weight of a backpack or fannypack to a wearer's waist by having a hip belt encircle the waist. Many of these previous efforts place a pad over the lumbar region of the spine and then use a hip belt to compress the pad against the lumbar portion of a wearer's spine. Examples of this technique can be seen in several patents such as those shown in French patent 2,669,519, U.S. Pat. No. 4,479,595, U.S. Pat. No. 5,228,609, and U.S. Pat. No. 5,236,112. Although the padding helps to protect the lumbar region of the spine, a problem still remains as the lumbar padding does not concentrate weight vertically along the complex curvature of the spine existing in the lumbar region. Because a hip belt rides just above the hips of a wearer, the hip belt also places a considerable load on the wearer's hip region.
A padded belt normally circles the waist of a wearer. Weight is distributed to the waist region when using a hip belt by compressing the padding into the waist along the longitudinal axis of the hip belt. Adjustments to the hip belt length merely changes the forces applied inwardly along the length of the belt. Even though the belt is padded, this does not permit for adjustable concentration of the weight of the pack vertically along the lumbar region of a wearer's spine. Because of the complex curvature of the lumbar, the use of additional belts circling the waist of a wearer will not concentrate the weight at the lumbar region of the wearer, because the force will be directed inwardly around the waist of the wearer along the length of the belt.
What is needed is a mechanism associated with the hip belt to concentrate weight vertically over the complex curvature of the lumbar region of a wearer's spine. The mechanism should be capable of adjustably changing the curvature of a lumbar pad to transfer weight effectively to the lumbar region of an individual, each having a uniquely shaped spine.